New Delhi, Dec 17 (ANI): A recent survey has found that 90 percent of the emails sent to a person's inbox are usually spam.
The survey report suggests that more and more hackers are devising new ways to send in spam emails, reports the China Daily.
It further states that virus-infected computers are woven into "botnets" used to attack more machines, and to send sales pitches to e-mail addresses in low-cost quests to bilk readers out of cash.
"Every year we see threats evolve as criminals discover new ways to exploit people, networks and the Internet," Cisco chief security researcher Patrick Peterson, who was involved in drafting the report, said.
According to the Cisco Annual Security Report, junk e-mail make up for nearly 200 billion messages daily, approximately 90 percent of email worldwide.
As per the survey, the US is the biggest source of spam, accounting for 17.2 percent messages.
Turkey and Russia ranked second and third, accounting for 9.2 percent and 8 percent spam respectively, according to Cisco.
This year, botnets were used to inject an array of legitimate websites with an IFrames malicious code that reroutes visitors to websites that download computer viruses into their machines.
"The botnet is, in many cases, ground-zero for online criminal threats," Peterson said.
"Using malware to infect someone's computers is an incredibly common mechanism and harnessing them all together is a way they do their click fraud, spam emails, and data stealing," he added.
Online criminals are turning botnets on web-based e-mail accounts. Hackers are "reputation hijacking" by using botnets to figure out weak passwords protecting web-based e-mail accounts, according to Peterson.
Weak passwords consist of family names, birthdays, home addresses or other terms considered relatively easy to deduce.
Once access is gained to legitimate e-mail accounts, a plethora of spam messages are sent in the owners' names. (ANI)